IBM Z10 EC Reference Manual page 50

Coupling Facility Confi guration Alternatives
IBM offers multiple options for confi guring a functioning
Coupling Facility:
• Standalone Coupling Facility : The standalone CF
provides the most "robust" CF capability, as the CPC is
wholly dedicated to running the CFCC microcode — all
of the processors, links and memory are for CF use
only. A natural benefi t of this characteristic is that the
standalone CF is always failure-isolated from exploiting
z/OS software and the server that z/OS is running on for
environments without System-Managed CF Structure
Duplexing. While there is no unique standalone coupling
facility model offered with the z10 EC, customers can
achieve the same physically isolated environment as on
prior mainframe families by ordering a z10 EC, z9 EC, z9
BC, and z990 with PUs characterized as Internal Cou-
pling Facilities (ICFs). There are no software charges
associated with such a confi guration.
• Internal Coupling Facility (ICF) : Customers consider-
ing clustering technology can get started with Parallel
Sysplex technology at a lower cost by using an ICF
instead of purchasing a standalone Coupling Facility.
An ICF feature is a processor that can only run Coupling
Facility Control Code (CFCC) in a partition. Since CF
LPARs on ICFs are restricted to running only CFCC,
there are no IBM software charges associated with
ICFs. ICFs are ideal for Intelligent Resource Director and
resource sharing environments as well as for data shar-
ing environments where System-Managed CF Structure
Duplexing is exploited.
System-Managed CF Structure Duplexing
System-Managed Coupling Facility (CF) Structure Duplexing
provides a general purpose, hardware-assisted, easy-to-
exploit mechanism for duplexing CF structure data. This pro-
vides a robust recovery mechanism for failures such as loss
of a single structure or CF or loss of connectivity to a single
CF, through rapid failover to the backup instance of the
duplexed structure pair. CFCC Level 16 provides CF Duplex-
ing enhancements described previously in the section titled
"Coupling Facility Control Code (CFCC) Level 16".
Parallel Sysplex Coupling Connectivity
The Coupling Facilities communicate with z/OS images in
the Parallel Sysplex environment over specialized high-
speed links. As processor performance increases, it is
important to also use faster links so that link performance
does not become constrained. The performance, avail-
ability and distance requirements of a Parallel Sysplex
environment are the key factors that will identify the appro-
priate connectivity option for a given confi guration.
When connecting between System z10, System z9 and
z990/z890 servers the links must be confi gured to operate
in Peer Mode. This allows for higher data transfer rates
to and from the Coupling Facilities. The peer link acts
simultaneously as both a CF Sender and CF Receiver link,
reducing the number of links required. Larger and more
data buffers and improved protocols may also improve
long distance performance.
. . . . . . . .
. . . . . . . . . . . .
HCA2-O HCA2-O
z10 EC z10 EC
50
12x 12x
PSIFB PSIFB
Up to 150 meters Up to 150 meters
1x 1x
PSIFB PSIFB
Up to 10/100 Km Up to 10/100 Km
12x 12x
PSIFB PSIFB
. . . . Up to 150 meters Up to 150 meters
z9 EC and z9 BC S07 z9 EC and z9 BC S07
HCA2-O LR HCA2-O LR
. . . . . . . . . . . . . . . . . . . . . . . .
HCA2-O HCA2-O
New ICB-4 cable New ICB-4 cable
ICB-4 10 meters ICB-4 10 meters
z10 EC, z10 BC, z9 EC, z10 EC, z10 BC, z9 EC,
MBA MBA
z9 BC, z990, z890 z9 BC, z990, z890
ISC-3 ISC-3
ISC-3 ISC-3
ISC-3 ISC-3
IFB-MP IFB-MP
ISC-3 ISC-3
HCA2-C HCA2-C
Up to 10/100 Up to 10/100
ISC-3 ISC-3
Km Km
I/O Drawer I/O Drawer
z10 EC, z10 BC, z9 EC, z10 EC, z10 BC, z9 EC,
z9 BC, z990, z890 z9 BC, z990, z890
z10 EC, z10 z10 EC, z10
BC BC